Three hours and 12 minutes is 3.2 hours. 12 minutes is one fifth of an hour (60/12 = 5) and one fifth is 0.2.
One fifth plus one fifth is two fifths (2/5).
one fifth
Five hours out of a twenty four hour day would be 5/24, or just slightly over one fifth of a day (if a day had 25 hours instead of 24, then five hours would be exactly one fifth of a day). As a decimal, 5 hours is .208333... of a 24 hour day.
one and one-fifth
one and fifth of an hour
72 minutes
12 Minutes.
One-fifth of the tank
20/5=4 4 is one fifth of 20
72 mins: 60 divided by 5 (1 fifth) is 12 mins, there's 60 mins in and hour, 60 + 12 = 72
The same as you calculate the fraction of anything. For example, a fifth of an hour is one part out of five equal parts of a whole hour.
My work will be completed in an hour and a half.
The Babylonians thought it was a good idea. Helped by the fact that 60 is divisible by several small integers so that it is easy to work out a quarter of an hour or a fifth.
Three hours and 12 minutes is 3.2 hours. 12 minutes is one fifth of an hour (60/12 = 5) and one fifth is 0.2.
24 seconds
Usually one hour per hour.